The £28 billion merger between BAE Systems and EADS was teetering last night as the chief executive of the British group flew into Toulouse ahead of an expected plea for more time to thrash out a deal.

The creation of the world’s largest aerospace and defence company was on a knife edge as it entered the last 24 hours before a deadline of 5pm this evening to come up with substantive merger proposals.

The deadline was set 28 days ago by the Takeover Panel under its “put up or shut up” rule, under which companies making a bid must clarify